Type I diabetes results from the body's failure to produce insulin, the hormone that "unlocks" the cells of the body, allowing glucose to enter and fuel them. It is estimated that 20.8 Million Americans have diabetes; type I diabetes accounts for 5 to 10%of cases (approximately 1.56 Million type I diabetic patients). Keeping blood glucose levels under tight control represents the most effective way either to prevent the onset or to reduce the progression of the chronic complications of type I diabetes, such as blindness, kidney failure and cardiovascular diseases. Islet transplantation can achieve insulin independence, glucose control and freedom of hypoglycemic attacks in patients afflicted with Type I diabetes mellitus. However, the recovery of functional pancreatic islets from cadaveric donor pancreata is a complex procedure and needs to be optimized. Until an unlimited source of human pancreatic islet cell becomes available, the further development of endocrine replacement therapy for the treatment of diabetes will solely depend on the availability of high quality islet preparations, both for clinical application and laboratory-based research. Because of the complexity of the islet isolation procedure, it would be desirable to concentrate the know-how in a limited number of centers or consortiums to allow for optimal use of available resources. The aim of this application is to extend the existing human islet core facility at the University of Illinois and the Chicago Islet Consortium into a federally funded Islet Cell Resource Center to isolate, purify, characterize and distribute human pancreatic islet cells for both transplantation into diabetic patients and use in laboratory studies to a larger community. The ICR at UIC with its partners in the Chicago Islet Consortium will be responsible for the procurement of whole pancreata, isolation and quality control of islet cell preparations, and distribution of islets for approved research or clinical protocols. The ICR at UIC is conducting research and development to improve isolation techniques, cellular viability and function, and shipping procedures, and is investigating methods for improved assessment of islet mass, composition, quality and viability. In addition, and most importantly for the progres of the field, the ICR at UIC will continue to provide large numbers of high-quality islet preparations for transplantation in diabetic patients.